In our complex society today, numerous systems rely upon electrical power to function properly. Under normal circumstances, operating power is provided by the commercial AC power distribution systems for heat, air conditioning, traffic lights, cooking, telecommunications, etc. Since many, if not all, major power distribution lines are located on poles or towers, a natural disaster, such as a tornado, hurricane, or blizzard, frequently causes the loss of commercial AC power. The failure of commercial AC power may constitute a significant danger to life or property depending upon the system impacted. For instance, failure of AC power supplying the lighting or air conditioning in a hospital or nursing home could readily result in loss of life. Therefore, backup power systems have been developed to assure that the loss of primary power does not seriously affect critical systems.
The one critical system which is most often taken for granted is the telecommunications system. Significantly, when an emergency occurs, virtually everyone expects that telephone communications will remain unaffected. Clearly this is essential; since it is through the telephone that we normally summon medical or rescue aid. Therefore, because of this essential nature, the telecommunications system has been provided with a complex backup power system in the event of commercial AC power failure.
Traditionally, backup electricity for telecommunications has been achieved by dispersing batteries throughout the telecommunications system to power the necessary switches, amplifiers, etc., of the system. These batteries, amounting to millions worldwide, may be located in special rooms, atop a telephone pole, or even atop a mountain, depending upon the local system needs. These batteries may be in place for years before a power failure requires them. These batteries, which are typically a lead-acid type, employ a very well understood and proven technology. However, the batteries still require physical maintenance from time to time, eventually do fail, and must be replaced. Because of the nature of the components, the batteries are inherently extremely heavy per unit volume. Some of the portable batteries used in telecommunications backup weigh as much as 120 pounds each. Additionally, the lead is very toxic and, when no longer useable, must be properly recycled. The acid electrolyte is also a significant hazard to those who must service the batteries, or to anyone who comes in contact with them. Therefore, handling the batteries must be as safe as possible with little chance of an accident. Dropping a battery could cause a very undesirable chemical spill, and cause possible injury to the technician.
Typically, telecommunications backup batteries are located within a steel case, with handles at opposing ends. However, as in many areas, an emphasis on optimal use of space drives a requirement to make the batteries and their cases as small as possible. Unfortunately, the batteries have been optimized to such an extent that the emphasis on space savings has shifted to the case. As the battery case is relatively thin steel, little can be done to reduce case size.
One area of the case that has only infrequent, although important, usage is the handle used for lifting. Whatever material is used for the handle, it must be: (a) resistant to the acid electrolyte in the batteries, (b) fire resistant, or at least not support combustion, and (c) of sufficient strength to support the battery weight. Previous handles have comprised metal, plastic, and synthetic cloth. Metal handles, although meeting all of the above criteria, are somewhat bulky, and thus do not help solve the space problem. Metal handles also will conduct electricity, and therefore pose something of an electrical shorting problem. Some plastics meet (b) and (c) above, but are not resistant to the acid. Most synthetic cloths, such as KEVLAR.RTM. and NOMEX.RTM. are also not acid resistant. The one material found to meet all of the above criteria is a fiber made of RYTON.TM. (polyphenylene sulfide--PPS). PPS has been successfully used for battery handles of the type described in U.S. Pat. No. 5,565,283 to Chalasani et al, However, the design of Chalasani requires a significant amount of PPS, which is quite expensive. Therefore, it would be highly desirable to produce a design which uses significantly less material for each handle.
Accordingly, what is needed in the art is a battery handle that is both fire and acid resistant, has a minimal profile, and is cheaper to manufacture than the current design.